Cartoning apparatus normally contain a magazine for receiving a supply of flat fielded carton blanks and apparatus for ejecting those carton blanks from the magazine and erecting them into a generally rectangular tubular form. The cartoner typically includes a pair of endless chains, one carrying leading transport lugs and the other carrying trailing transport lugs. In such apparatus, a carton is erected and captured between the leading and trailing transport lugs. The carton is then held between these lugs as it passes through a filling station.
As the carton passes through the filling station, a barrel loader thrusts product into the carton, and as it passes through a gluing and flap closing apparatus, the carton is sealed. However, if a carton as it is transported through the sealing stages is not square, the flaps are misaligned on the resulting package making it an unsightly or unacceptable package.
In typical applications, cartoners require frequent changeovers for running different sizes of cartons. In the changeover, mechanics use wrenches to loosen parts, slip the parts relative to one another and re-tighten the parts to fix them in that position. For example, the chain carrying the leading lug is physically shifted with respect to the chain carrying the trailing lugs to accommodate cartons of greater or lesser length. In this case, length refers to the dimension in the direction of machine movement, i.e., the carton width taken across the face or front panel of a carton.
In addition, the cartons used for cereals or the like may vary in front to back depth or thickness and height. Therefore, it is difficult and time consuming to manually adjust the various guide bars in order to accommodate different sizes of cartons. It is difficult because of adjustments for the carton finishing operations, such as flap closing and sealing. The cartons must be properly aligned, the cartons "squared" and brought into register with a filler for the loading operation. It is also difficult because carton conveying and loading apparatus are typically of considerable length, and because there are a large number of steps to be performed at different points along the length of the machine.
The U.S. Pat. No. 4,642,975 of Langen et al. discloses one approach to a carton loading machine which facilitates the adjustment of the machine to accommodate cartons of different sizes. In that machine, retainer bars are arranged along at least three sides of a square configuration of a carton's pathway and are mounted for simultaneous movement with respect to a plurality of receptacles so that the spacing between the retainer bar and the oppositely disposed wall of the receptacle can be adjusted to accommodate articles of different sizes.
It has now been found that a carton conveyor and loading apparatus in accordance with the present invention offers a number of advantages over the prior art. For example, such apparatus fixes the tipper rear surface and trailing corner of a carton so that any adjustments are made with respect to that corner. The use of the upper, inner or rear and trailing corner facilitates the alignment of carton finishing and filling apparatus as well as the distance between cartons based along a transport chain. This spacing along the chain is important since each carton must be brought into register with the filling apparatus.
The conveyor in accordance with the present invention may also include means for simultaneous lateral adjustment of an outer guide rail along its entire length and of an intermediate member which carries carton finishing apparatus. Such adjustments may be readily accomplished manually or by a programmed computer. For example, a change to accommodate a carton of a specific size can be preprogrammed so that an operator of minimal skill merely indicates a carton number, and the machine will adjust itself to the preprogrammed setting for that carton.
The mechanism disclosed and claimed herein may also incorporate an adjustable pocket mechanism such as those claimed in my copending application Ser. No. 08/336,671, filed on Nov. 7, 1994, entitled "Adjustable Pocket Mechanism" which is assigned to the same assignee as the present invention and which is incorporated herein in its entirety by reference.
Furthermore, it is presently believed that the carton conveyor in accordance with the present invention can be manufactured at a competitive price, will be relatively compact, easily adjustable and operable by a relatively unskilled employee. In addition, such apparatus is believed to be relatively durable and easily serviced.